Safety devices for tension springs

ABSTRACT

Safety devices for loose attachment to each end of garage-doormounted coiled tension spring(s) such as used to lift overhead doors. Separated (severed) pieces of spring assembly which result from accidental break and would otherwise fly about the area are retained by the safety device, thus preventing property and personal injury. Different forms of device are provided for attachment to single and to double springs, in either event comprising a rockable cradle or bracket which embraces the spring hanger, plus it journals and anchors a cross pin which traverses the terminal spring attachment loop(s), which loop is also hung on the conventional hanger. The cross pin is limitedly movable axially to the spring so as to accommodate attachment loops of different sizes. Such safety devices can be placed on already mounted spring assemblies without disassembling the latter.

United States Patent Smith et al.

[is] 3,656,737 [4 1 Apr. 18, 1972 [54] SAFETY DEVICES FOR TENSION SPRINGS 3,575,404 4/1971 Wesch ..267/74 Primary Examiner-James B. Marbert Attomey-l-loward L. Johnson [57] ABSTRACT Safety devices for loose attachment to each end of garagedoor-mounted coiled tension spring(s) such as used to lift overhead doors. Separated (severed) pieces of spring assembly which result from accidental break and would otherwise fly about the area are retained by the safety device, thus preventing property and personal injury. Different forms of device are provided for attachment to single and to double springs, in either event comprising a rockable cradle or bracket which embraces the spring hanger, plus it journals and anchors a cross pin which traverses the terminal spring attachment |o0p(s), which loop is also hung on the conventional hanger. The cross pin is limitedly movable axially to the spring so as to accommodate attachment loops of different sizes. Such safety devices can be placed on already mounted spring assemblies without disassembling the latter.

5 Claims, 5 Drawing Figures SAFETY DEVICES FOR TENSION SPRINGS BACKGROUND OF THE INVENTION This invention relates to simple and readily installed safety devices which can be added to (each end of) coiled tension springs, such as those spring assemblies mounted on overhead garage doors to facilitate or balance their easy opening and closing. Such springs necessarily embody a very appreciable tensile force which if accidently released (as by breakage) may severely injure or maim a person standing nearby, may break auto windows or other glass, dent auto bodies, sever electric lines, and do other damage. If the remaining attached end of the stretched and broken spring. happens to be turned tachment to the door or to the stationary wall, and likewise fly off.

For such problem the present invention provides a unit which in its preferred form can be added to an already installed spring assembly without in any way disturbing the latter, and which being loosely connected thereto does not in any way change the normal operation of the spring. By retainfing each end of the spring, should the spring be severed at in intermediate point, both ends are still securely held by the present device. Altemately, should the spring break at one of its attachment ends, it is still held at the other end, and in addition the disconnected hanger is also retained.

As noted in the preceding abstract, the invention provides a cradle structure (hanger support) which is capable of limited rocking movement relative to or caused by normal pivotal swing of the hanger in its normal use. A coacting element is a separate cross pin which is inserted loosely through the attachment loop of the coil or coils, and received and retained in slots of the cradle, which slots are directed axial to the coiled springsthus to allow its limited movement lengthwise to the coil so as to accommodate coil attachment loops of different sizes; that is, the safety device can be placed on mounted spring assemblies having diverse size attachment loops, or can be transferred from one assembly to another.

The accompanying drawings illustrate two forms of the safety device which are applied respectively to a single coiled spring assembly (with S-hanger), and to a double coiled spring assembly (with A-hanger), wherein FIG. 1 is an axial sectional view taken through a single coil, tension spring showing in elevation one of the present safety devices attached to each end thereof.

FIG. 2 is a section and elevational view taken at 90 rotation of the longitudinal axis of FIG. 1.

FIG. 3 is an elevational view of one end of a double coil atvtachment with the present cradle element appearing in longitudinal section taken along the line 3-3 of FIG. 5.

FIG. 4 is an end view as seen from the right of FIG. 3.

FIG. 5 is a top plan view of the safety device of FIG. 3 as viewed along the line 5--5.

The construction shown in FIGS. 1-2 employs a single spring coil. 8 suspended between a pair of S-hangers 10, 10a. Each end of the coil has an attachment loop l1, 12 which is engaged by the inner end of the respective S-hanger. The outer end of each hanger respectively is hooked over the rivet or pivot pin 13 of a sheave 14, or over the tenninal link 15 of a chain 16 or other attachment. Generally one attachment 14 is secured to a fixed element such as a door jamb or wall, and the other attachment 16 is connected to a movable member such as a door or louver assembly (not shown).

For use with such construction, the present invention provides a stirrup-shaped cradle 18 which is formed of a generally U-shaped flat metal strip, having the end of each arm 19, 20 formed with an elongated slot 21 (FIG. 2) and the intermediate curved portion 17 adapted to be received loosely between the side plates 6, 7 of the sheave so as to overlie the hook 9 of the hanger l0 and the pivot pin 13. It will be seen arm that the arcuate portion 17 has a greater span and radius than the underlying hook 9 of the hanger 10 so as to extend beyond it at each end. Also the mounted cradle 18 can easily move lengthwise between the parallel sheave plates 6, 7 so as to achieve self-adjustment during use, but in addition the free end of each arm 19, 20 is formed with a lateral extension 22 (FIG. 2) which provides a limit for movement of an arm through the sheave (without first turning the arm as is done for initial installation). Altemately the curved portion 17a can be installed in the attachment loop 12 of the coil as seen in the lower part of FIG. 2. In either event, it will be seen that the loosely carried cradle 18 rocks or conforms with the combination swinging and lengthwise movement of the coil, without being subject to the strain that the'coil is under.

A retaining pin 24, 24a is inserted through each aligned pair of slots 21. One end of the pin is formed with a flared head 23, 23a and the other end 25, 25a is threaded so as to receive a locking element such as a wing nut 26, 26a thereon. Each pin is also inserted through the connecting element of the adjacent hanger hook, that is, the attachment loop 11 and the chain link 15. Washer elements W may also be provided and the pin secured at whatever location along the slots 22 which accommodates the longitudinal span between the pin 24 and arc 17 without crowding the loop 11 and hanger 10 (or the hanger 10a and link 15, as the case may be). If desired, a separate figure 8 or double link 27 may be traversed by the cross pin 24 and the adjacent hook 28 of the hanger 10. In the event that the hook 9 should be kicked off of the rivet 13 by a spring break, the link 27 retains the hanger 10 from flying off.

In the construction shown in FIGS. 3-5 there are two parallel coil springs 30, 32, the respective attachment loops 31, 33 of which are jointly held by the curved arms 34, 35 of an A- hanger 36 (one such hanger being at each end of the pair of springs, but only one here shown for simplicity). The saddle portion 37 of the hanger (FIG. 4) overlies a rivet 38 which connects two spaced hanger plates 39, 40. For use with such assembly, the present invention provides a cradle 42 formed as an elongated, transverse, generally rectangular channel having an outer end face 43 and generally parallel sides 44, 45. The end face 43 (or top as appearing in plan in FIG. 5) is formed with a longitudinal slot 46 adjacent one edge, open at one end 47, which slot serves to receive and center the two arms or midportion of the A-hanger 36. Along the opposite, longitudinal edge of the end plate are two openings 48, 49 through which the upturned ends of the hanger arms 34, 35 loosely project. The parallel side walls 44, 45 are each formed with a pair of elongated slots 50, 51 (FIG. 3), aligned with each other across the channel and spaced apart similar to the distance between the coil loop support positions of the two hanger arms 34, 35. Accordingly a retaining pin 52, 53 can each be inserted (loosely) through one of the coil attachment loops 31 or 32 and at the same time jointly through one of the aligned pair of side wall slots 50 or 51. As before, each pin has a headed end 54, 55 and a wing nut 56, 57 mounted on the opposite, threaded end. Accordingly it will be seen that the cradle is loosely retained on the hanger assembly, accommodating itself to but not interfering with its normal movement (as determined for example by opening and closing of the attached door), with the cradle not being subject to the strain and tension of spring operation. However should either (or both) the springs be accidently severed at some point, the safety device will automatically restrain 'the disconnected pieces from flying about. With this (A) type hanger construction, the hanger itself does not readily detach from the rivet and hanger plates 39, 40; but without the present cradle 42, upon breakage of one coil (30 or 32) the unsevered coil might be jerked to such an unbalanced position that its attachment loop (31 or 33) becomes disconnected from the hanger arm (34 or 35).

I claim:

1. A safety device of the character described, for loose connection jointly to a hanger or hanger-mount and to the attachment loop of a coiled tension spring which is movably held by said hanger, said device comprising in combination:

a cradle adapted to spacedly overlie said hanger at least on opposite sides thereof, and a pin adapted to loosely traverse said hanger-mounted spring attachment loop and to be adjustably retained by said overlying cradle, whereby the pin may be located adjustable longitudinally to said coil and thus attachment loops of a different size can be accommodated by the device.

2. A safety device according to claim 1 wherein said cradle is fonned with a channel having a transverse surface connecting the opposite, overlying portions and formed with openings disposed to receive therein, respectively a pair of arms and the upturned ends thereof of an A-hanger, each of which arms is adapted to support an attachment loop of a coiled tension spring within said channel, and which pin is thus adapted jointly to traverse the attachment loops of the two coiled tension springs.

3. A safety device according to claim-l in combination with an S-shaped hanger, plus a loose linkage element connecting said pin and S-hanger.

4. A safety device according to claim 1 including a channelshaped cradle having a transverse end surface formed with a longitudinal slot open at one end for reception therein of the two arms of anA-hanger, which arms support the attachment loops of a pair of coiled tension springs.

5. A safety device of the character described for use with an adjacent pair of coiled tension springs which are terminally suspended by an A-hanger:

an elongated chanel-shaped cradle, the floor of the channel being formed .with a longitudinal slot for. reception therein of the two arms of an A-hanger, and with other openings in the channel floor transversely spaced therefrom for projection of the respective turned-up ends of the arms of the A-hanger, upon the respective A-arms each traversing a terminal attachment loop of one of said coils when the loops are received in said channel,

and a pair of transverse pins each extending through one of said attachment loops and anchored loosely in the sides of said channel for adjustment longitudinal to said coils, whereby attachment loops of different size may be accommodated in the channel.

l0l032 mu 

1. A safety device of the character described, for loose connection jointly to a hanger or hanger-mount and to the attachment loop of a coiled tension spring which is movably held by said hanger, said device comprising in combination: a cradle adapted to spacedly overlie said hanger at least on opposite sides thereof, and a pin adapted to loosely traverse said hanger-mounted spring attachment loop and to be adjustably retained by said overlying cradle, whereby the pin may be located adjustable longitudinally to said coil and thus attachment loops of a different size can be accommodated by the device.
 2. A safety device according to claim 1 wherein said cradle is formed with a channel having a transverse surface connecting the opposite, overlying portions and formed with openings disposed to receive therein, respectively a pair of arms and the upturned ends thereof of an A-hanger, each of which arms is adapted to support an attachment loop of a coiled tension spring within said channel, and which pin is thus adapted jointly to traverse the attachment loops of the two coiled tension springs.
 3. A safety device according to claim 1 in combination with an S-shaped hanger, plus a loose linkage element connecting said pin and S-hanger.
 4. A safety device according to claim 1 including a channel-shaped cradle having a transverse end surface formed with a longitudinal slot open at one end for reception therein of the two arms of an A-hanger, which arms support the attachment loops of a pair of coiled tension springs.
 5. A safety device of the character described for use with an adjacent pair of coiled tension springs which are terminally suspended by an A-hanger: an elongated chanel-shaped cradle, the floor of the channel being formed with a longitudinal slot for reception therein of the two arms of an A-hanger, and with other openings in the channel floor transversely spaced therefrom for projection of the respective turned-up ends of the arms of the A-hanger, upon the respective A-arms each traversing a terminal attachment loop of one of said coils when the loops are received in said channel, and a pair of transverse pins each extending through one of said attachment loops and anchored loosely in the sides of said channel for adjustment longitudinal to said coils, whereby attachMent loops of different size may be accommodated in the channel. 